Marine Habitats Correlation

There are two marine habitat classification systems that are commonly used in the UK: EUNIS, for work related to European obligations, and the JNCC Marine Habitat Classification for Britain and Ireland. These classification schemes define all the marine habitats known to occur in the UK. Lists of marine habitats that are of particular importance to conservation have been defined under various legislative instruments. These include:

It is often necessary to translate between EUNIS and the JNCC Marine Habitat Classification for Britain and Ireland, or to identify which habitats from these classifications would qualify as a listed habitat. In order to do this, JNCC have created correlation tables between different systems, stating the relationship between different habitats.

Two tools have been created to investigate these marine habitat correlations: the correlation spreadsheet and the correlation database. These two tools contain the same correlations, and are updated biannually in September and March.

If you would like to suggest any changes to the correlations contact JNCC at

The marine habitat correlations (as presented in both tools) should be cited as:

JNCC (2016) Marine Habitat Correlation Tables Version 2016.09 [Online]. [Date accessed]. Available from:


Correlation Spreadsheet

The marine habitats correlation spreadsheet allows users to translate from the EUNIS marine classification to the Marine Habitat Classification for Britain and Ireland and listed marine habitats. The user can search for and filter certain habitats. The supporting cover note provides more information about how the correlation table should be used.


In 2015, JNCC added a deep-sea section to the Marine Habitat Classification for Britain and Ireland. These deep-sea habitats differ from those in the EUNIS classification. The main correlation table in the spreadsheet shows how each EUNIS deep-sea habitat correlates with JNCC deep-sea habitats. In addition, a JNCC deep-sea habitat to listed habitat correlation table is provided in a separate tab within the spreadsheet. This provides more detail on exactly how JNCC deep-sea habitats relate to listed habitats.


Click to download the marine habitats correlation spreadsheet
(version 2.0; updated September 2016)


Correlation Database

 This tool stores marine habitat correlations in a database format and allows easy filtering and searching. It contains the same correlations as the spreadsheet version, with some additional information about habitats.

Click to download the marine habitats correlation database
(version 2.0;  updated September 2016)


The database has three functions, which you can select when you open the database:

1.    Show habitats in individual classification

2.    Show matrix between classifications

3.    Show individual habitat correlations

 Correlations main

1. Show habitats in individual classification

This allows you to quickly find all the habitats in a particular classification, and get a description of them, e.g. if you want to remind yourself what all the MCZ FOCI are, or what the definition for Blue Mussel Beds is. Simply click on “Show habitats in individual classification” then select the classification you are interested in from the drop down list.

2. Show matrix between classifications

This allows you to translate from any one classification to another; e.g. if you know an MPA has certain EUNIS habitats and want to check if any may be classed as an MCZ HOCI.

Just click on “Show matrix between classifications” then select the two classifications you want to correlate from drop down lists. You can filter the ‘From Habitat Name’ or ‘To Habitat Name’ column to select just those habitats you are interested in.

3. Show individual habitat correlations

This allows you to select a particular habitat and see which habitats from other classifications a correlated with it; e.g. if you want to make a map of OSPAR Lophelia Pertusa Reefs using biotope point samples and need to check which biotopes meet the criteria.

Click on “Show matrix between classifications” then chose a habitat classification from the drop down list, and a specific habitat from the drop down list below. You can filter the ‘To classification’ column to select just those habitats from a particular classification.

correlation OSPAR

Example output from the 'show individual habitat correlations' function

You can export an output as an excel or text file using the icons in the top left hand corner.

IMPORTANT: note that habitat correlation tools give an indication of which biotopes may be classed as a listed habitat, but remember that additional specific criteria may apply (e.g. the habitat may have to be a certain size) so you should always check detailed listed habitat definitions to make sure.